There is a debate about whether particular properties are for Aristotle non-recurrent and trope-like individuals or recurrent universals. I argue that Physics I.7 provides evidence that he took non-substantial particulars to be neither; they are instead non-recurrent modes. Physics I.7 also helps show why this matters. Particular properties must be individual modes in order for Aristotle to preserve three key philosophical commitments: that objects of ordinary experience are primary substances, that primary substances undergo genuine change, and that primary substances are (...) ontologically fundamental. (shrink)